Albeet dboit



(No Model.) 2 Sheets-Sheet 1.

A. DROIT.

eALGINlNG APPARATUS.

No. 370,326. Patented Sept. 20, 1887.

N. Fzvzns. Pmmumegnphef, washington. n. cv

(No Model.) v2 sheets-sheet 2.

A.` DROIT.

GALGINING APPARATUS.

10,370,320 Patented Sept. 2o, 188m AUnire STATES ATENT Erica.

ALBERT DROIT, OF PARIS, FRANCE.

CALCINING APPARATUS.

jSPIECIPICATON forming part of Letters Patent No. 370,326, datedSeptember 20, 1887.

1 Application filed Julyli, i887. Serial No. 244,237. (No model.)

To all whom it may concern:

Be it known that I, ALBERT DROIT, a citizen of the Republic of France,residing in Paris, in said Republic, have invented a new and usefulImprovement in Apparatus for Calcining Carbonate of Soda and otherSubstances, of which the following is a specification, reference beinghad to the accompanying drawings. A

This invention has especially for its object the calcination of thebicarbonate of soda obtained by the ammonia process. tions to befulfilled in such calcination are as follows: First, it is necessary totreat large quantities of the bicarbonate at a time; sec- -ond, thebicarbonate is a bad conductor of heat, and to heat itin all its partsit is necessary to stir it to prevent the formation of crusts on theheated surface; third, the appara tus should permit the collection ofthe gas and vapor disengaged; fourth, the product having to be calcinedhighly to have a convenient density, the apparatus is quickly destroyed,and it is necessary to construct it as durable as possible to facilitatethe repair.

4 The apparatuses heretofore employed to cal eine by direct heating aregenerally formed of a cast-iron kettle or of a horizontal cylinder.These apparatuses are fixed. The heating being direct, the fire strikesupon arestricted surface and the iron is quickly burned. The soda isstirred by very complicated agitators,which incompletely scrape theheated surfaces, because of the rapid deformation which the apparatusesare subject to under the influence of the heat.

My invention consists in the combinatiom' The condi-v an arched furnace,F, heated by a fireplace which ranges along the whole length of one sideof it. This cylinder is mounted on four rollers, Gi, keyed upon twohorizontal shafts, Adr'. One of these shafts receives a continuousrotary motion, which -it communicates to the cylinder C* by theintermediation of the roll ers Gi The axis of the cylinder C* istraversed by the shaftB*,which receives a rotary motion in a reversedirection to that of the cylinder. This shaft passes throughastufiing-box in one end ofthe cylinder, said stuffing-box beingfurnished with asbestus packing. It is supported at its other extremityby a fixed tubular bearing, Tik, inserted through the other end of thecylinder. A second stuffing-box packed with asbestus prevents the escapeof gas at this end.

The shaft B* carries two cast-i ron blades, Lit, carried by arms L,articulated by pivots r* toiianges B,keyed on the shaft. These blades bytheir own weight -scrape the surface of the cylinder duringaboutahalf-revolution, andin order that their action may be moreenergetic they are formed with numerous teeth in the direction of theirlength, the teeth of one blade corresponding with the spaces on theother blade.

The tube T* carries a nozzle, Mik, which is keyed to it, and whichdebouches in the upper part of the cylinder.

The charging and discharging of the bicarbonate into and from thecylinder are made by two doors, Ph, provided in one of the heads, andfurnished with means for making them airtight. The exit of the gas,whichis disengaged during the reaction, takes place through the nozzle Miiand the fixed tube Tik.

A shaft, Nik, receiving motion through a pulleyand belt, carries anendless screw which gears with a wheel, 0*. Two pinions, H* HW, mountedon the same shaft with the wormwheel 0*, communicate their movement, thefirst to the shaft B* through the intermediation of the wheel I* on thesaid shaft, and the second to the cylinder C* by the intermediation ofthe wheel Kf. This latter pinion H2* may slide on its shaft in order topermit the throwing out of gear when it is required to charge ordischarge the cylinder.

ICO

The advantages which result from the emthe rotary shaft fitted tobearings in the ends ployment of this apparatus are considerable; ofsaid cylinder and having flanges B Within the rotary cylinder is heateduniformly, and the said cylinder, the arms F', pivoted to said 15consequently is more durable. The deeomanges, the Scrapers IRF, carriedby said arms,

5 position of the bicarbonate willbemore rapid, vand theinclosing-furnace F, having the fire- `because the heating-surface isgreater. The place on one side, substantially as herein dearticulatedand toothed stirrers produce an scribed. energetic stirring and preventthe formation of adherent erusts of soda.

1o What I claim as myinvention, and desire to Witnesses:

secure by Letters Patent, is- PAUL CURALF,

The combination of the rotary cylinder 0*, LOUIs QUn'rREHoMMEs.

ALBERT DROIT.

